Fall Webworms and Bagworms
What to do about them!
Searcy, Ark. – Two insect pests of trees that are being spotted right now are the fall webworm (Hyphantria cunea) and the bagworm (Thyridopteryx ephemeraeformis). These terms can create confusion as people will sometimes refer to webworms as "bagworms" due to the encased webbing they form. Both are caterpillars of native moths.
Fall webworms form their nests in the tips of tree branches and are generally only of aesthetic concern, not requiring treatment. These native caterpillars favor sweetgum, crabapples, persimmons, black walnut, pecan, hickory, cherry, river birch and occasionally even elms and willows. To further add to the confusion, Eastern tent caterpillars (Malacosoma americanum) are also sometimes referred to as "bagworms" or "webworms". While they more closely resemble fall webworms, their lifecycle is different. These caterpillars and their nests appear in crotches of trees in spring, and unlike fall webworms, they will leave their nest to feed. They are generally not considered a destructive pest even though they may defoliate a tree. Their nests can be removed during the early morning and late evening when the caterpillars in the nest.
Bagworm cocoons are not similar in appearance to fall webworm webs or eastern tent caterpillar tents. Bagworms enclose themselves in spindle-shaped cocoons and partially emerge to consume foliage but are rarely seen. The first symptom people tend to notice is defoliation and then upon close examination spot the bags hanging from branches. Bagworm-infested plants may require treatment, however, once bags are observed, picking the bags off by hand is the only option. Bagworms typically attack juniper, arborvitae, cedars, cypress, pine, hemlock, and spruce. Broadleaved plants that may be attacked include apple, basswood, black locust, boxelder, elm, honey locust, Indian hawthorn, maple, various oaks, persimmon, sumac, sycamore, wild cherry, willow and azalea.
For more information you can contact your local county extension service, you can also follow Sherri Sanders @UAEX.WhiteCountyAgriculture on Facebook. The Arkansas Cooperative Extension Service is an equal opportunity/equal access/affirmative action institution.
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By Sherri Sanders
County Extension Agent - Agriculture
The Cooperative Extension Service
U of A System Division of Agriculture
Media Contact: Sherri Sanders
County Extension Agent - Agriculture
U of A Division of Agriculture
Cooperative Extension Service
2400 Old Searcy Landing Road Searcy AR 72143
(501) 268-5394
ssanders@uada.edu
The Arkansas Cooperative Extension Service is an equal opportunity/equal access/affirmative
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